The goal of this NIH SBIR Phase II Grant Application is to expand and validate the pilot in vitro neurotoxicity database that was constructed during a Phase I SBIR Grant. The toxicity database will be used to aid in evaluating the safety characteristics of new chemical compounds that may be therapeutically administered to humans or that pose significant exposure potential to human populations through their use. Commercially, this database will be offered by NOVASCREEN Biosciences Corp. to the pharmaceutical, chemical, agricultural and biotech industries to reduce costs and streamline their toxicity testing requirements. The scope of this Phase II will be further in vitro toxicity testing of a select group of compounds used in Phase I and the screening of an additional 800 new compounds in two cell lines that are of neural origins. This testing will include assays that measure cellular growth, metabolism, respiration, viability and apoptosis. Annotations derived from the literature on animal and human in vivo toxicity testing standard compounds as well as assay data from NOVASCREEN's own proprietary receptor screening database (RSM) will be incorporated into this toxicity database. [unreadable] [unreadable]